jjj0923 wrote:I found that this worked fine though:
convert dim.jpg -fill white -colorize 50% results.jpg
That is not transparency fading, but fading to 'white'.
For a image destined for viewing on a white background such as in a browser, that will work fine, and even work better
for older Internet Explorers that did not handle PNG transparency right. Or for JPEG images which does not handle transparency at all!.-alpha
functionality, providing many.-matte
is equivelent to -alpha set
which is what you should be using.
So try this...
Code: Select all
convert dim.jpg -matte -channel a -evaluate set 50% results.jpg
You should NOT use -alpha on
unless you know what you are doing. It is too basically too simple!
ASIDE: For new images -alpha set
and -alpha on
are equivelent. But for old images possibility containing old alpha channels -alpha on
can cause problems you should use -alpha set
, which will ensure alpha is present, but does not change the current look of the image if an old alpha channel was present.
For more details see IM Examples, Basics
, Controlling Image Transparencyhttp://www.imagemagick.org/Usage/basics/#alpha